[Federal Register: August 16, 2007 (Volume 72, Number 158)]
[Proposed Rules]
[Page 45949-45952]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr16au07-16]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2007-28942; Directorate Identifier 2007-NM-093-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-100, -200, -200C, -
300, -400, and -500 Series Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for certain Boeing Model 737-100, -200, -200C, -300, -400, and -500
series airplanes. This proposed AD would require repetitive detailed
and high-frequency eddy current inspections for cracking around the
heads of the fasteners on the forward fastener row of certain areas of
the station (STA) 259.5 circumferential butt splice, and repair if
necessary. This proposed AD would also require a preventive
modification, which would eliminate the need for the repetitive
inspections. This proposed AD results from a report that an operator
found multiple cracks in the fuselage skin of a Model 737-200 airplane,
at the forward fastener row of the STA 259.5 circumferential butt
splice between stringers 19 and 24. We are proposing this AD to prevent
cracking of the STA 259.5 circumferential butt splice, which could
result in loss of structural integrity of the fuselage skin and
possible loss of cabin pressure.
DATES: We must receive comments on this proposed AD by October 1, 2007.
ADDRESSES: Use one of the following addresses to submit comments on
this proposed AD.
DOT Docket Web site: Go to http://dms.dot.gov and follow
the instructions for sending your comments electronically.
Government-wide rulemaking Web site: Go to http://www.regulations.gov
and follow the instructions for sending your
comments electronically.
Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590.
Fax: (202) 493-2251.
Hand Delivery: Room W12-140 on the ground floor of the
West Building, 1200 New Jersey Avenue, SE., Washington, DC, between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle,
Washington 98124-2207, for the service information identified in this
proposed AD.
FOR FURTHER INFORMATION CONTACT: Wayne Lockett, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
917-6447; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
[[Page 45950]]
Comments Invited
We invite you to submit any relevant written data, views, or
arguments regarding this proposed AD. Send your comments to an address
listed in the ADDRESSES section. Include the docket number ``Docket No.
FAA-2007-28942; Directorate Identifier 2007-NM-093-AD'' at the
beginning of your comments. We specifically invite comments on the
overall regulatory, economic, environmental, and energy aspects of the
proposed AD. We will consider all comments received by the closing date
and may amend the proposed AD in light of those comments.
We will post all comments we receive, without change, to http://dms.dot.gov
, including any personal information you provide. We will
also post a report summarizing each substantive verbal contact with FAA
personnel concerning this proposed AD. Using the search function of
that Web site, anyone can find and read the comments in any of our
dockets, including the name of the individual who sent the comment (or
signed the comment on behalf of an association, business, labor union,
etc.). You may review DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78), or you
may visit http://dms.dot.gov.
Examining the Docket
You may examine the AD docket on the Internet at http://dms.dot.gov
, or in person at the Docket Operations office between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays. The
Docket Operations office (telephone (800) 647-5527) is located on the
ground floor of the West Building at the DOT street address stated in
the ADDRESSES section. Comments will be available in the AD docket
shortly after the Docket Management System receives them.
Discussion
We have received a report indicating that an operator found
multiple cracks in the fuselage skin of a Model 737-200 airplane that
had accumulated 69,350 total flight cycles. The cracking was found at
the forward fastener row of the station (STA) 259.5 circumferential
butt splice between stringers 19 and 24, and some cracks had joined
into one large crack. This condition, if not corrected, could result in
loss of structural integrity of the fuselage skin and possible loss of
cabin pressure.
Relevant Service Information
We have reviewed Boeing Special Attention Service Bulletin 737-53-
1267, dated November 28, 2006. The service bulletin describes
procedures for doing repetitive detailed and high-frequency eddy
current (HFEC) surface inspections for cracking around the heads of the
fasteners on the forward fastener row of certain areas of the STA 259.5
circumferential butt splice, and applicable repair if necessary.
Certain areas of the circumferential butt splice are those described in
the Accomplishment Instructions of Service Bulletin 737-53-1267 as
areas that have not had a preventive modification installed in
accordance with Boeing Service Bulletin 737-53-1076, or have not had a
Boeing, FAA-approved repair accomplished.
The service bulletin also describes procedures for doing a
preventive modification of certain areas of the STA 259.5
circumferential butt splice, including removing the existing fasteners,
doing an HFEC rotary probe inspection of the fastener holes, and, if no
crack is found, oversizing the holes and installing new protruding head
fasteners. The preventive modification eliminates the need for the
repetitive inspections.
The service bulletin specifies compliance times that depend upon
the number of total flight cycles accumulated by the airplane.
Compliance times for doing the initial inspections begin at or before
the accumulation of 50,000 total flight cycles, with grace periods
ranging between 500 and 4,500 flight cycles after the release date of
the service bulletin. The service bulletin specifies that repetitive
inspections shall be done thereafter at intervals of 9,000 flight
cycles, until the preventive modification is done. The service bulletin
specifies that all repairs are to be done before further flight and
that the preventive modification is to be done before the accumulation
of 75,000 total flight cycles or within 6,000 flight cycles after the
release date of the service bulletin, whichever comes later.
Accomplishing the actions specified in the service information is
intended to adequately address the unsafe condition.
FAA's Determination and Requirements of the Proposed AD
We have evaluated all pertinent information and identified an
unsafe condition that is likely to exist or develop on other airplanes
of this same type design. For this reason, we are proposing this AD,
which would require accomplishing the actions specified in the service
information described previously.
Costs of Compliance
There are about 2,150 airplanes of the affected design in the
worldwide fleet. The following table provides the estimated costs for
U.S. operators to comply with this proposed AD, at an average labor
rate of $80 per work hour. Required parts would be supplied by the
operator.
Estimated Costs
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Number of U.S.-
Action Work Cost per airplane registered Fleet cost
hours airplanes
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Inspection........................... 5 $400, per inspection 654 $261,600, per
cycle. inspection cycle.
Preventive modification.............. 24 $1,920.................. 654 $1,255,680.
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Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, Section 106, describes the
authority of the FAA Administrator. Subtitle VII, Aviation Programs,
describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701, ``General
requirements.'' Under that section, Congress charges the FAA with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce. This regulation is within
the scope of that authority because it addresses an unsafe condition
that is likely to exist or develop on
[[Page 45951]]
products identified in this rulemaking action.
Regulatory Findings
We have determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD would not
have a substantial direct effect on the States, on the relationship
between the national Government and the States, or on the distribution
of power and responsibilities among the various levels of government.
For the reasons discussed above, I certify that the proposed
regulation:
1. Is not a ``significant regulatory action'' under Executive Order
12866;
2. Is not a ``significant rule'' under the DOT Regulatory Policies
and Procedures (44 FR 11034, February 26, 1979); and
3. Will not have a significant economic impact, positive or
negative, on a substantial number of small entities under the criteria
of the Regulatory Flexibility Act.
We prepared a regulatory evaluation of the estimated costs to
comply with this proposed AD and placed it in the AD docket. See the
ADDRESSES section for a location to examine the regulatory evaluation.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by
adding the following new airworthiness directive (AD):
Boeing: Docket No. FAA-2007-28942; Directorate Identifier 2007-NM-
093-AD.
Comments Due Date
(a) The FAA must receive comments on this AD action by October
1, 2007.
Affected ADs
(b) Accomplishing repairs and modifications described in
paragraphs (f) and (g) of this AD is considered acceptable for
compliance with repair requirements of paragraphs (f) and (g) of AD
92-25-09, amendment 39-8424, for the areas of the station (STA)
259.5 circumferential butt splice only.
Applicability
(c) This AD applies to Boeing Model 737-100, -200, -200C, -300,
-400, and -500 series airplanes, certificated in any category, as
identified in Boeing Special Attention Service Bulletin 737-53-1267,
dated November 28, 2006.
Unsafe Condition
(d) This AD results from a report that an operator found
multiple cracks in the fuselage skin of a Model 737-200 airplane, at
the forward fastener row of the STA 259.5 circumferential butt
splice between stringers 19 and 24. We are issuing this AD to
prevent cracking of the STA 259.5 circumferential butt splice, which
could result in loss of structural integrity of the fuselage skin
and possible loss of cabin pressure.
Compliance
(e) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.
Inspections
(f) At the applicable initial compliance time specified in
paragraph 1.E. ``Compliance'' of Boeing Special Attention Service
Bulletin 737-53-1267, dated November 28, 2006, except as provided by
paragraph (j) of this AD: Do detailed and high-frequency eddy
current inspections for cracking around the heads of the fasteners
on the forward fastener row of certain areas of the station (STA)
259.5 circumferential butt splice, by doing all of the actions
specified in Part 1 of the Accomplishment Instructions of the
service bulletin, except as provided by paragraph (i) of this AD.
Repeat the inspections thereafter at the intervals specified in
paragraph 1.E. of the service bulletin. Doing the preventive
modification specified in paragraph (h) of this AD terminates the
repetitive inspection requirements of this paragraph.
Repair
(g) If any crack is found during any inspection required by this
AD, before further flight, repair in accordance with Part 1 of the
Accomplishment Instructions of Boeing Special Attention Service
Bulletin 737-53-1267, dated November 28, 2006.
Preventive Modification
(h) At the compliance time specified in paragraph 1.E. of Boeing
Special Attention Service Bulletin 737-53-1267, dated November 28,
2006, except as provided by paragraph (j) of this AD: Do the
preventive modification in accordance with the Accomplishment
Instructions of Boeing Special Attention Service Bulletin 737-53-
1267, dated November 28, 2006. Doing the preventive modification
terminates the repetitive inspections required by paragraph (f) of
this AD.
Modification or Repair Done in Accordance with AD 92-25-09
(i) Inspections described by paragraph (f) of this AD are not
required for areas of the STA 259.5 circumferential butt splice that
have been modified in accordance with the service information
specified in Table 1 of this AD. (Boeing Service Bulletin 737-53-
1076, Revision 4, dated September 26, 1991, is cited as an
appropriate source of service information for doing certain
requirements of AD 92-25-09.)
Table 1.--Service Information
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Boeing Service Bulletin Revision level Date
----------------------------------------------------------------------------------------------------------------
737-53-1076........................... 4.................................. September 26, 1991.
737-53-1076........................... 3.................................. September 20, 1990.
737-53-1076........................... 2.................................. February 8, 1990.
737-53-1076........................... 1.................................. November 23, 1988.
737-53-1076........................... Original Issue..................... October 30, 1986.
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Compliance Times
(j) Where the service bulletin specifies compliance times
relative to the release date of Boeing Special Attention Service
Bulletin 737-53-1267, dated November 28, 2006, this AD requires
compliance at compliance times relative to the effective date of
this AD.
Alternative Methods of Compliance (AMOCs)
(k)(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested in
accordance with the procedures found in 14 CFR 39.19.
(2) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Before using any approved AMOC on any airplane to which the AMOC
applies, notify your appropriate principal inspector (PI) in the FAA
Flight Standards District Office (FSDO), or lacking a PI, your local
FSDO.
(3) An AMOC that provides an acceptable level of safety may be
used for any repair required by this AD, if it is approved by an
Authorized Representative for the Boeing
[[Page 45952]]
Commercial Airplanes Delegation Option Authorization Organization
who has been authorized by the Manager, Seattle ACO, to make those
findings. For a repair method to be approved, the repair must meet
the certification basis of the airplane, and the approval must
specifically refer to this AD.
Issued in Renton, Washington, on July 30, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E7-16104 Filed 8-15-07; 8:45 am]
BILLING CODE 4910-13-P